#ifndef __API_CPP_H
#define __API_CPP_H

#include <iostream>

using std::endl;
using std::cout;
using ostream=std::ostream;

class C {
public:
    C();
    C& operator+=(int v) { num+=v; return *this; } 
    C& operator-=(int v) { num-=v; return *this; } 
private:
    int num;
    static int cnt;
    friend ostream& operator<<(ostream &out, const C& c);
};

#endif //__API_CPP_H
